NEETChemistryAmines
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): N-methylaniline reacts with Hinsberg's reagent to yield a product that is insoluble in aqueous NaOH. Reason (R): The sulphonamide formed by the reaction of a secondary amine with Hinsberg's reagent lacks an acidic hydrogen atom. In the light of the above statements, choose the most appropriate answ
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A).
- BBoth (A) and (R) are true but (R) is not the correct explanation of (A).
- C(A) is true but (R) is false.
- D(A) is false but (R) is true.
Correct answer
A. Both (A) and (R) are true and (R) is the correct explanation of (A).
Step-by-step solution
N-methylaniline ( C₆H₅NHCH₃ ) is a secondary ( 2^ ) amine. It reacts with Hinsberg's reagent (benzenesulphonyl chloride, C₆H₅SO₂Cl ) to form N-methyl-N-phenylbenzenesulphonamide. Because there is no hydrogen atom attached to the nitrogen in this sulphonamide, it lacks an acidic hydrogen. Therefore, it is insoluble in aqueous alkali (NaOH). Thus, both Assertion (A) and Reason (R) are true, and (R) is the correct explanation of (A). Answer: Both (A) and (R) are true and (R) is the correct explanation of (A).